Simple Expression Parser Bill Bauldry Dept of Mathematical Sciences Appalachian State University BauldryWC@appstate.edu

This worksheet implements a simple parser for Maple expressions. The output is a nested list that describes how Maple interprets the expression. The syntax is simple: Parse(expression). The Parse function can be used to learn about expression evaluation and Maple's internal expression data structures.

The Op function replaces an item with a form: [operation, operand list] QyQ+SSNPcEc2ImYqNiNJInhHRiVGJUYlRiVAJzMyIiIiLUklbm9wc0clKnByb3RlY3RlZEdGJzQtSSV0eXBlR0YvNiRGKEkpZnVuY3Rpb25HRi83JC1JKXdoYXR0eXBlR0YlRictSSNvcEdGL0YnRjE3JC1GOTYkIiIhRihGOEYoRiVGJUYlISIi The Parse function recursively traverses the expression generating a nested list of [operation, operands] pairs in essentially prefix notation. QyQ+SSZQYXJzZUc2ImYqNiNJJWV4cHJHRiU2JEkkdG1wR0YlSSJpR0YlRiVGJUMlPkYqLUkjT3BHRiVGJz8oRisiIiMiIiItSSVub3BzRyUqcHJvdGVjdGVkRzYjRipJJXRydWVHRjVAJDUyRjItRjQ2IyZGKjYjRistSSV0eXBlR0Y1NiRGPUkpZnVuY3Rpb25HRjU+RiotSSdzdWJzb3BHRjU2JC9GKy1GJEY8RiotSSdSRVRVUk5HRjVGNkYlRiVGJSEiIg== LUklbXJvd0c2Iy9JK21vZHVsZW5hbWVHNiJJLFR5cGVzZXR0aW5nR0koX3N5c2xpYkdGJzYjLUkjbWlHRiQ2JVEhRicvJSdpdGFsaWNHUSV0cnVlRicvJSxtYXRodmFyaWFudEdRJ2l0YWxpY0Yn

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print();

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print();

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print();

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print();

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